Diamond compacts

Abstract

Diamond compact composed of 60-95 volume % diamond crystals plastically deformed into a closely packed, rigid structure with contacts between the diamond crystals over extended mating surfaces arising from the plastic deformation. The diamond crystals are bonded together by an interstitial bonding material composed of a refractory carbide, such as silicon carbide, or a bonding material composed of a metal such as rhenium and a refractory carbide formed by reaction of a metallic bonding agent, such as tungsten, with carbon.

What is claimed is: 
     
       1. A diamond compact for cutting, turning, drilling, and otherwise working ultra-hard ceramics, carbides and rocks comprised to 60-95 volume percent of diamond crystals which have been plastically deformed so that they form a closely packed framework structure in which contacts between diamond crystals occur over extended mating surfaces arising from plastic deformation of the diamond crystals during formation of the compact under pressure and temperature conditions within the graphite stability field, the diamond crystals being bonded together by interstitial bonding material comprised of (1) a metal selected from the group consisting of rhenium, rhodium, ruthenium, iridium, osmium and platinum which has accepted carbon from the diamond crystals into solid solution and has formed a bond having a melting point exceeding 1600° C., and (2) a refractory carbide formed by reaction of a metallic bonding agent with carbon in the diamond crystals during formation of the compact under said pressure and temperature conditions, said compacting comprising less than about 2 percent volume of graphite and possessing a compressive strength greater than 10 kbars. 
     
     
       2. A diamond compact as claimed in claim 1, wherein said metal is rhenium and said metallic bonding agent is tungsten. 
     
     
       3. A diamond compact as claimed in claim 1, wherein said metal is iridium and said metallic bonding agent is tungsten. 
     
     
       4. A diamond compact for cutting, turning, drilling, and otherwise working ultra-hard ceramics, carbides and rocks, comprises of 60-95 volume percent of diamond crystals which have been plastically deformed so that they form a closely packed rigid structure in which contacts between the diamond crystals occur over extending mating surfaces arising from plastic deformation of the diamond crystal during formation of the compact under pressure and temperature conditions within the graphite stability field, the diamond crystals being bonded together by interstitial bonding material comprising a refractory carbide formed by reaction of a bonding agent with carbon in the diamond crystals during formation of the compact under said pressure and temperature conditions, said carbide having a minimum melting point greater than 1600° C. in the presence of carbon and said compact comprising less than about 2 percent volume of graphite and possessing a compressive strength greater than 10 kbars. 
     
     
       5. A diamond compact for cutting, turning, drilling and otherwise working ultra-hard ceramics, carbides and rocks, comprised of 60-95 volume percent of diamond crystals which have been plastically deformed so that they form a closely packed rigid structure in which contacts between the diamond crystals occur over extended mating surfaces arising from plastic deformation of the diamond crystals during formation of the compact under pressure and temperature conditions within the graphite stability field, the diamond crystals being bonded together by interstitial bonding materials comprising silicon carbide formed by reaction of a silicon rich bonding agent with carbon in the diamond crystals during formation of the compact under said pressure and temperature conditions, said silicon carbide having a minimum melting point greater than 1600° C. in the presence of carbon and said compact comprising less than about 2 percent volume of graphite and possessing a compressive strength greater than 10 kbars. 
     
     
       6. A diamond compact for cutting, turning, drilling, and otherwise working ultra-hard ceramics, carbides and rocks comprised of 60 to 95 volume percent of diamond crystals which have been plastically deformed so that they form a closely packed framework structure in which contacts between diamond crystals occur over extended mating surfaces arising from plastic deformation of the diamond crystals during formation of the compact under pressure and temperature conditions within the graphite stability field, the diamond crystals being bonded together by interstitial bonding material comprised of a metal selected from the group consisting of rhenium, rhodium, ruthenium, iridium, osmium and platinum which has accepted carbon from the diamond crystals into solid solution and has formed a bond having a melting point exceeding 1600° C., said compact comprising less than about 2 percent volume of graphite and possessing a compressive strength greater than 10 kbars. 
     
     
       7. A diamond compact as claimed in claim 6 wherein said metal is rhenium.